A heat exchanger regulating system and regulating method with coupling control

Abstract

The application discloses a heat exchanger adjusting system and adjusting method of coupling control, relates to the technical field of heat exchange adjusting control, and comprises a heat exchanger; a water inlet of the heat exchanger is connected with a cold and hot source pipe network, and a water outlet is connected with an electric regulating valve; the pressure sensor comprises a first pressure sensor and a second pressure sensor, and is respectively installed at the water inlet end and the water outlet end of the electric regulating valve; the temperature sensor comprises a first temperature sensor and a second temperature sensor, and is respectively installed on a primary side water supply pipeline and a return water pipeline of the heat exchanger; the electric regulating valve is installed on the return water pipeline of the heat exchanger; the room temperature controller and the temperature sensor transmit the temperature difference signal of the room temperature set value and the actual value to the micro control unit and the BMS; the micro control unit calculates the valve opening degree instruction through the built-in coupling control algorithm and outputs to the driver. The problems of pipe network hydraulic coupling interference and system control lag of the existing heat exchanger adjusting system under the premise that no external physical flow meter is needed are solved.

Description

Technical Field

[0001] This invention belongs to the field of heat exchange regulation and control technology, specifically relating to a coupled control heat exchanger regulation system and regulation method. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] In central air conditioning water systems and district heating or cooling systems, heat exchangers, as key devices connecting heat sources and air conditioning terminals, directly determine indoor comfort and the overall system's energy efficiency through precise operation and regulation. Scientific and rational adjustment of heat exchange flow can effectively counteract hydraulic interference and reduce system energy waste, resulting in a wide range of applications and significant economic value.

[0004] Currently, automatic regulation technology for heat exchangers has been widely adopted due to its ability to achieve basic temperature control. Its control logic typically relies on a building automation system (BMS) to perform proportional-integral-derivative (PID) control calculations based on room temperature deviations, directly mapping this to valve opening commands. However, in actual operation, this traditional control method heavily depends on installing external physical flow meters to obtain feedback data, increasing system costs and subsequent maintenance burdens. Furthermore, fluctuations in pipeline flow cause dynamic nonlinear changes in pipeline series resistance, distorting the inherent flow characteristics of valves. Single-loop control is prone to response lag, and both of these factors severely restrict the comprehensive regulation level of heat exchange systems under complex hydraulic conditions. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a coupled-control heat exchanger regulation system and method. Based on three types of sensor information—pressure difference monitoring before and after the valve, supply and return water temperature difference monitoring, and indoor temperature monitoring—the system uses a built-in coupling algorithm to control the valve opening, achieving precise flow regulation and load matching. This solves the problems of hydraulic coupling interference in the pipe network and system control lag in existing heat exchanger regulation systems without the need for external physical flow meters.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, the present invention provides a coupled-controlled heat exchanger regulation system, comprising: a heat exchanger, a pressure sensor, a temperature sensor, a driver, an electric regulating valve, a room thermostat, and a microcontroller unit; the primary side inlet of the heat exchanger is connected to a cold / heat source pipeline network, and the primary side outlet is connected to the electric regulating valve; the pressure sensor includes a first pressure sensor and a second pressure sensor, respectively installed at the inlet and outlet ends of the electric regulating valve; the temperature sensor includes a first temperature sensor and a second temperature sensor, respectively installed on the primary side supply and return water pipelines of the heat exchanger; the electric regulating valve is installed on the return water pipeline of the heat exchanger; the room thermostat, pressure sensor, temperature sensor, and BMS communicate with the microcontroller unit to set a target indoor temperature and collect the actual indoor temperature in real time, and set the room temperature value. T s Compared with actual value T a The temperature difference signal is transmitted to the microcontroller unit and BMS; the microcontroller unit calculates the valve opening command through the built-in coupling control algorithm and outputs it to the driver to control the opening of the electric regulating valve and realize variable flow heat exchange operation.

[0007] As a further implementation, both the first pressure sensor and the second pressure sensor output a differential pressure analog signal; both the first temperature sensor and the second temperature sensor output a temperature analog signal.

[0008] As a further implementation, the microcontroller unit is installed inside the driver and is communicatively connected to the first pressure sensor, the second pressure sensor, the first temperature sensor, the second temperature sensor, the room thermostat, and the BMS. The microcontroller unit has a built-in analog-to-digital conversion unit, a flow calculation and verification unit, and a water temperature calculation unit, and is programmed with a PID correction control program to receive and process the differential pressure analog signal collected by the pressure sensor, the water temperature signal from the temperature sensor, the room temperature signal from the room thermostat, and the heat exchange intensity signal from the BMS.

[0009] Secondly, the present invention also provides a regulation method for a coupled-controlled heat exchanger regulation system, comprising the following steps: The system collects the primary side supply water temperature of the heat exchanger detected by the first temperature sensor, the return water temperature detected by the second temperature sensor, the inlet water pressure of the electric regulating valve detected by the first pressure sensor, the outlet water pressure detected by the second pressure sensor, and the actual indoor temperature detected by the room thermostat. The temperature difference signal between the room temperature setpoint and the actual value is transmitted to the microcontroller and BMS. The analog-to-digital conversion is performed on the pressure difference analog signal between the inlet and outlet water pressures to calculate the real-time pressure difference before and after the electric regulating valve; the analog-to-digital conversion is performed on the water temperature analog signals between the supply and return water temperatures to calculate the supply and return water temperature difference; and the actual heat exchange load of the heat exchanger is calculated using the energy equation. The system receives the target demand load from the BMS, compares the actual heat exchange load with the target demand load to obtain the load deviation, presets the allowable range of load deviation, maintains the current valve opening when the absolute value of the load deviation does not exceed the allowable range of load deviation, and when the absolute value of the load deviation exceeds the allowable range of load deviation, the PID control module dynamically calculates the valve action direction and adjustment step size with the load deviation as input and outputs the valve opening command. The actuator receives the valve opening command and drives the electric regulating valve to adjust the valve opening. The first pressure sensor, the second pressure sensor, the first temperature sensor, and the second temperature sensor continuously collect dynamic parameters and transmit them back to the microcontroller unit. The real-time pressure difference and supply and return water temperature difference data are updated cyclically. The real-time flow rate and actual heat exchange load are calculated and verified simultaneously until the load deviation enters the preset control dead zone. The actuator then stops operating and maintains the current valve opening.

[0010] As a further implementation, when calculating the real-time flow rate, a valve authority is introduced to perform hydraulic correction on the flow rate estimation. The relative opening and the valve authority are substituted into the built-in nonlinear impedance equation to convert the static pipeline impedance coefficient into a dynamic comprehensive impedance coefficient. The real-time flow rate is then calculated by combining the real-time pressure difference to eliminate characteristic distortion errors.

[0011] As a further implementation, the inherent adjustable ratio of the equal percentage flow characteristic and the inherent impedance coefficient of the electric regulating valve in the fully open state are preset in the microcontroller unit in the nonlinear impedance equation.

[0012] As a further implementation, when the electric regulating valve is at its fully open or fully closed limit position, an anti-integral saturation program is started to pause the integral term accumulation calculation of the PID regulating module. Normal accumulation of the integral term is resumed after the electric regulating valve exits the limit position.

[0013] As a further implementation, the PID control module adopts a room temperature-load deviation cascaded PID control algorithm, which includes an outer loop PID control module and an inner loop PID control module. The outer loop PID control module takes the room temperature deviation as input and dynamically outputs the target demand load; the inner loop PID control module takes the load deviation as input and dynamically outputs the valve opening command; the outer loop PID control module and the inner loop PID control module are nested and cascaded for coordinated control.

[0014] As a further implementation, the outer loop PID control module is used to compensate for the temperature response lag caused by building thermal inertia, ensuring the steady-state control accuracy of the terminal room temperature; the inner loop PID control module is used to quickly respond to changes in the hydraulic conditions of the pipeline network and suppress hydraulic coupling interference.

[0015] As a further implementation, the first pressure sensor, the second pressure sensor, the first temperature sensor, and the second temperature sensor continuously collect dynamic parameters after changes in the pipeline network and heat exchange, and transmit the pressure analog signal and temperature analog signal back to the microcontroller unit in real time. Through analog-to-digital conversion, the real-time pressure difference and supply and return water temperature difference data are continuously updated, and the adjusted real-time flow rate and actual heat exchange load are calculated and verified simultaneously, so that the actual heat exchange load continuously approaches the target demand load. When the load deviation enters the preset control dead zone range, the actuator stops operating and maintains the current valve opening.

[0016] Compared with the prior art, the advantages and positive effects of this invention are: This invention uses a microcontroller unit built into the driver to perform multi-parameter coupling calculations, achieving accurate acquisition of heat exchange flow rate without the need for an external physical flow meter. This fundamentally avoids the maintenance and calibration problems caused by the long-term operation of traditional hardware flow meters, and significantly reduces the hardware procurement cost and subsequent maintenance burden of the heat exchange system.

[0017] This invention addresses the distortion of valve characteristics caused by changes in the hydraulic conditions of the pipeline network. It introduces valve authority for in-depth hydraulic correction and transforms static pipeline impedance into dynamic comprehensive impedance coefficient through a built-in coupling algorithm. This overcomes the limitations of traditional physical flow meters and single static impedance formulas, achieving accurate flow soft estimation with anti-distortion even without physical flow meters, and realizing dynamic matching of heat exchange intensity and end-user heating and cooling loads.

[0018] This invention employs a room temperature-load cascaded PID control algorithm, dividing the control process into an outer loop room temperature control and an inner loop load control for nested coordination. The outer loop effectively compensates for the temperature response lag caused by building thermal inertia, while the inner loop quickly responds to changes in the hydraulic conditions of the pipe network and directly suppresses hydraulic coupling interference. This not only eliminates the delay caused by multi-level control but also overcomes the defects of "slow dynamic response" and "poor steady-state accuracy" that are easily caused by traditional single-loop control, achieving a balance between rapid response to hydraulic fluctuations in the primary side of the pipe network and steady-state accuracy of the room temperature at the end. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0020] Figure 1This is a block diagram of the coupled control heat exchanger regulation system of the present invention; Figure 2 This is a control flowchart of the coupled control heat exchanger regulation system of the present invention.

[0021] In the diagram: 1. Heat exchanger; 2. Electric regulating valve; 3. First pressure sensor; 4. Second pressure sensor; 5. First temperature sensor; 6. Second temperature sensor; 7. Driver; 8. Microcontroller unit; 9. Room thermostat. Detailed Implementation

[0022] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0023] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is intended to include the plural form as well. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0024] Example 1 This embodiment provides a coupled control heat exchanger regulation system, such as Figure 1 The system includes: a heat exchanger 1, a pressure sensor, a temperature sensor, a driver 7, an electric regulating valve 2, a room thermostat 9, and a microcontroller unit 8. The heat exchanger 1 has its primary side inlet connected to a cold / heat source network and its primary side outlet connected to the electric regulating valve 2 for heat exchange. The pressure sensor includes a first pressure sensor 3 and a second pressure sensor 4, installed at the inlet and outlet of the electric regulating valve 2 respectively, for real-time detection of the water pressure before and after the valve and outputting a corresponding differential pressure analog signal. The temperature sensor includes a first temperature sensor 5 and a second temperature sensor 6, installed on the primary side supply and return water lines of the heat exchanger 1 respectively, for real-time detection of the supply and return water temperatures and outputting a corresponding temperature analog signal. The electric regulating valve 2 is installed on the return water line of the heat exchanger 1. The room thermostat 9, pressure sensor, temperature sensor, and BMS communicate with the microcontroller unit 8 to set the target indoor temperature and collect the actual indoor temperature in real time, setting the room temperature. T s Compared with actual value T aThe temperature difference signal is transmitted to the microcontroller 8 and the BMS; the microcontroller 8 calculates the valve opening command through the built-in coupling control algorithm and outputs it to the driver 7 to control the opening of the electric regulating valve 2 and realize variable flow heat exchange operation.

[0025] The first pressure sensor 3 and the second pressure sensor 4 both output pressure difference analog signals; the first temperature sensor 5 and the second temperature sensor 6 both output temperature analog signals.

[0026] The microcontroller unit 8 is installed inside the driver 7 and is communicatively connected to the first pressure sensor 3, the second pressure sensor 4, the first temperature sensor 5, the second temperature sensor 6, the room thermostat 9, and the BMS. The microcontroller unit 8 has a built-in analog-to-digital conversion unit, a flow calculation and verification unit, and a water temperature calculation unit, and is programmed with a PID correction control program to receive and process the differential pressure analog signal collected by the pressure sensor, the water temperature signal from the temperature sensor, the room temperature signal from the room thermostat 9, and the heat exchange intensity signal from the BMS.

[0027] Example 2 This embodiment provides a regulation method for a coupled-controlled heat exchanger regulation system, such as... Figure 2 As shown, it includes the following steps: The primary side supply water temperature of heat exchanger 1 is collected by the first temperature sensor 5. T 1. The return water temperature detected by the second temperature sensor 6 T 2. The physical quantity of water temperature is converted into an analog signal and transmitted to the microcontroller unit 8; the water pressure at the inlet of the electric regulating valve 2 is collected by the first pressure sensor 3. P 1. The water pressure at the outlet detected by the second pressure sensor 4 P 2. Convert the physical quantity of pressure into an analog signal and transmit it to the microcontroller unit 8; collect the actual indoor temperature detected by the room thermostat 9. T a Set the room temperature value T s Compared with actual value T a The temperature difference signal is transmitted to the microcontroller unit 8 and the BMS; Regarding the P 1 and P The differential pressure analog signal of valve 2 is converted from analog to digital to calculate the real-time differential pressure before and after the electric regulating valve 2. P， .

[0028] To overcome the calculation errors caused by the constant impedance model used in conventional flow estimation, the microcontroller 8 incorporates the core characteristic parameters of the regulating valve. In actual hydraulic networks, the series resistance of the pipeline changes dynamically and nonlinearly with the increase or decrease of flow, which inevitably distorts the ideal equal percentage flow characteristics of the valve, leading to inaccurate flow calculations. To accurately reproduce actual operating conditions, the microcontroller 8 introduces valve authority for deep hydraulic correction.

[0029] In the specific calculation process, the microcontroller 8, based on the equal percentage flow characteristic, calculates the real-time relative opening. K v With valve authority a The coupling calculation is performed by substituting the input into the built-in nonlinear impedance equation. This model transforms the static pipeline impedance coefficient into a dynamic composite impedance coefficient. S The coupling formula of its internal logic is as follows:

[0030] in R The inherently adjustable ratio for equal percentage flow characteristics. S 0 represents the inherent impedance coefficient of the electric regulating valve 2 in the fully open state, which is preset in the microcontroller unit 8.

[0031] The system incorporates the dynamically corrected overall impedance coefficient S With real-time differential pressure P The real-time flow rate, after eliminating characteristic distortion errors, was calculated. G 1, G The formula for calculating 1 is as follows:

[0032] By dynamically correcting the nonlinear mapping relationship between valve opening and fluid impedance through mathematical modeling, the limitations of the traditional single static impedance formula are broken, and the accuracy of heat exchange flow rate estimation under complex hydraulic conditions is greatly improved.

[0033] The digital circuitry of the microcontroller 8 is for the... T 1 and T The analog water temperature signal is converted from analog to digital to calculate the supply and return water temperature difference. The actual heat transfer load of heat exchanger 1 is calculated using the energy equation. Q a ; Q a The calculation formula is as follows:

[0034] c p The specific heat capacity of water, ρThe density of water; the microcontroller unit 8 receives the target load demand from the BMS. Q t The calculated actual heat exchange load Q a With the target demand load Q t Comparison yields load deviation Q , Q The calculation formula is .

[0035] To prevent frequent operation of the electric regulating valve 2 due to minor load fluctuations, the microcontroller unit 8 presets a load deviation allowable range. Q d When the load deviation Q The absolute value does not exceed the allowable range of the load deviation. Q d When the system is considered to have reached a stable control state, the current valve opening is maintained, and the load deviation... Q The absolute value exceeds the allowable range of the load deviation. Q d At that time, the PID control module adjusts according to the load deviation. Q To input the dynamic calculation of valve action direction and adjustment step size and output valve opening command; when When the actual heat exchange load is lower than the target demand load, an instruction to increase the valve opening is output; when When the actual heat exchange load is higher than the target demand load, a command to reduce the valve opening is output; when At this time, no new adjustment command is output, and the current valve opening is maintained.

[0036] When the electric regulating valve 2 is at its fully open or fully closed limit position, the microcontroller unit 8 initiates an anti-integral saturation program, suspending the accumulation of the integral term to prevent control overshoot or response lag caused by integral saturation. Once the valve exits the saturation zone, the normal accumulation of the integral term resumes. By directly coupling the load deviation for feedforward-feedback regulation, the system eliminates the delay caused by multi-stage control, achieving precise dynamic control of heat exchange intensity.

[0037] The coupled regulation based on load deviation is further configured as a cascaded PID regulation based on room temperature and load deviation: the microcontroller unit 8 employs a room temperature-load cascaded PID control algorithm, dividing the control process into an outer room temperature control loop and an inner load control loop for nested cascaded coordinated control. The outer loop PID control module uses the room temperature deviation as the input parameter. , t For time, dynamically calculate and output the target demand load signal. The calculation formula is:

[0038] In the formula K This is the PID proportional gain coefficient. T I The integral time constant is... T D The time constant is the differential, and in the formula... K , T I , T D It can be obtained through software PID self-tuning; where t This represents the current running time of the system. τ It is a dummy variable for integration, representing any historical moment within the integration interval; e ( t )for t Temperature deviation at any given time; e ( τ (A historical moment) τ The corresponding room temperature control deviation.

[0039] To correct and compensate for temperature response lag caused by building thermal inertia in real time; the inner loop PID control module acts as a secondary loop, based on load deviation. Q The input parameter is the real-time target demand load output from the high-frequency receiver outer loop. The actual heat exchange load is calculated in real time by combining the valve pressure difference and the supply and return water temperature difference of heat exchanger 1. Q a The valve opening command of the electric regulating valve 2 is dynamically calculated and output.

[0040] The outer loop control effectively compensates for the temperature response lag caused by building thermal inertia, ensuring the steady-state control accuracy of the terminal room temperature; the inner loop control can quickly respond to changes in the hydraulic conditions of the pipe network and suppress hydraulic coupling interference. The two work together to achieve a balance between rapid response to the hydraulic conditions of the primary pipe network and steady-state accuracy of the terminal room temperature, overcoming the shortcomings of "slow dynamic response" and "poor steady-state accuracy" in traditional single-loop control.

[0041] The actuator 7 receives the final valve opening control command output by the microcontroller 8 (derived from single-loop load deviation or cascaded room temperature-load deviation calculation), converts the electrical signal into a mechanical action, drives the electric regulating valve 2 to adjust the valve opening, and drives the valve stem displacement of the electric regulating valve 2. The actuator 7 adjusts the relative valve opening according to the adjustment direction and step size set in the command: when the system determines that the current heat exchange intensity is insufficient, it increases the valve opening to increase the primary side water flow through the heat exchanger 1; when it determines that the heat exchange intensity is excessive, it decreases the valve opening to reduce the water flow through the heat exchanger 1.

[0042] The first pressure sensor 3, the second pressure sensor 4, the first temperature sensor 5, and the second temperature sensor 6 continuously collect dynamic parameters and transmit them back to the microcontroller unit 8, cyclically updating the real-time differential pressure. P Simultaneously calculate and verify real-time flow rate based on supply and return water temperature difference data. G 1 and actual heat exchange load Q a Until the load deviation enters the preset control dead zone, the actuator 7 stops operating and maintains the current valve opening.

[0043] The system repeats the above steps cyclically to adjust the actual heat exchange load. Q a Continuing to target demand load Q t Approaching. When the load deviation (or the combined room temperature and load deviation) enters the preset control dead zone range, the actuator 7 stops operating and maintains the current valve opening. At this time, the heat exchange intensity of the heat exchanger 1 achieves precise dynamic matching with the actual load demand at the terminal, thereby realizing the high steady-state operation of the system under the premise of eliminating hydraulic coupling interference.

[0044] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A coupled-controlled heat exchanger regulation system, characterized in that, include: The system comprises a heat exchanger, a pressure sensor, a temperature sensor, a driver, an electric regulating valve, a room thermostat, and a microcontroller unit. The heat exchanger's primary side inlet is connected to a cold / heat source network, and its primary side outlet is connected to the electric regulating valve. The pressure sensor includes a first pressure sensor and a second pressure sensor, respectively installed at the inlet and outlet of the electric regulating valve. The temperature sensor includes a first temperature sensor and a second temperature sensor, respectively installed on the primary side supply and return water lines of the heat exchanger. The electric regulating valve is installed on the return water line of the heat exchanger. The room thermostat, pressure sensor, temperature sensor, and BMS communicate with the microcontroller unit to set a target indoor temperature and collect the actual indoor temperature in real time. The temperature difference signal between the setpoint and the actual room temperature is transmitted to the microcontroller unit and the BMS. The microcontroller unit calculates the valve opening command using a built-in coupling control algorithm and outputs it to the driver to control the opening of the electric regulating valve, achieving variable flow heat exchange operation.

2. The coupled control heat exchanger regulation system according to claim 1, characterized in that, Both the first pressure sensor and the second pressure sensor output analog pressure difference signals; both the first temperature sensor and the second temperature sensor output analog temperature signals.

3. The coupled control heat exchanger regulation system according to claim 2, characterized in that, The microcontroller unit is installed inside the driver and is communicatively connected to the first pressure sensor, the second pressure sensor, the first temperature sensor, the second temperature sensor, the room thermostat, and the BMS. The microcontroller unit has a built-in analog-to-digital conversion unit, a flow calculation and verification unit, and a water temperature calculation unit, and is programmed with a PID correction control program to receive and process the differential pressure analog signal collected by the pressure sensor, the water temperature signal from the temperature sensor, and the room temperature signal from the room thermostat.

4. The regulation method for a coupled-controlled heat exchanger regulation system as described in any one of claims 1-3, characterized in that, Includes the following steps: The system collects the primary side supply water temperature of the heat exchanger detected by the first temperature sensor, the return water temperature detected by the second temperature sensor, the inlet water pressure of the electric regulating valve detected by the first pressure sensor, the outlet water pressure detected by the second pressure sensor, and the actual indoor temperature detected by the room thermostat. The temperature difference signal between the room temperature setpoint and the actual value is transmitted to the microcontroller and BMS. The analog-to-digital conversion is performed on the pressure difference analog signal between the inlet and outlet water pressures to calculate the real-time pressure difference before and after the electric regulating valve; the analog-to-digital conversion is performed on the water temperature analog signals between the supply and return water temperatures to calculate the supply and return water temperature difference; and the actual heat exchange load of the heat exchanger is calculated using the energy equation. The system receives the target demand load from the BMS, compares the actual heat exchange load with the target demand load to obtain the load deviation, presets the allowable range of load deviation, maintains the current valve opening when the absolute value of the load deviation does not exceed the allowable range of load deviation, and when the absolute value of the load deviation exceeds the allowable range of load deviation, the PID control module dynamically calculates the valve action direction and adjustment step size with the load deviation as input and outputs the valve opening command. The actuator receives the valve opening command and drives the electric regulating valve to adjust the valve opening. The first pressure sensor, the second pressure sensor, the first temperature sensor, and the second temperature sensor continuously collect dynamic parameters and transmit them back to the microcontroller unit. The real-time pressure difference and supply and return water temperature difference data are updated cyclically. The real-time flow rate and actual heat exchange load are calculated and verified simultaneously until the load deviation enters the preset control dead zone. The actuator then stops operating and maintains the current valve opening.

5. The adjustment method according to claim 4, characterized in that, When calculating the real-time flow rate, valve authority is introduced to perform hydraulic correction on the flow rate estimation. The relative opening and the valve authority are substituted into the built-in nonlinear impedance equation to convert the static pipeline impedance coefficient into a dynamic comprehensive impedance coefficient. The real-time flow rate is calculated by combining the real-time pressure difference to eliminate characteristic distortion errors.

6. The adjustment method according to claim 5, characterized in that, In the nonlinear impedance equation, the inherent adjustable ratio of the equal percentage flow characteristic and the inherent impedance coefficient of the electric regulating valve in the fully open state are preset in the microcontroller unit.

7. The adjustment method according to claim 4, characterized in that, When the electric regulating valve is at its fully open or fully closed limit position, the anti-integral saturation program is activated, pausing the integral term accumulation calculation of the PID regulating module. Normal accumulation of the integral term is resumed after the electric regulating valve exits its limit position.

8. The adjustment method according to claim 4, characterized in that, The PID control module employs a room temperature-load deviation cascaded PID control algorithm, which includes an outer-loop PID control module and an inner-loop PID control module. The outer-loop PID control module takes the room temperature deviation as input and dynamically outputs the target load demand. The inner-loop PID control module takes the load deviation as input and dynamically outputs valve opening commands. The outer-loop PID control module and the inner-loop PID control module are nested and cascaded for coordinated control.

9. The adjustment method according to claim 8, characterized in that, The outer loop PID control module is used to compensate for the temperature response lag caused by building thermal inertia and ensure the steady-state control accuracy of the terminal room temperature; the inner loop PID control module is used to quickly respond to changes in the hydraulic conditions of the pipeline network and suppress hydraulic coupling interference.

10. The adjustment method according to claim 4, characterized in that, The first pressure sensor, the second pressure sensor, the first temperature sensor, and the second temperature sensor continuously collect dynamic parameters after changes in the pipeline network and heat exchange. They transmit the pressure analog signal and temperature analog signal back to the microcontroller unit in real time. Through analog-to-digital conversion, they continuously update the real-time pressure difference and supply and return water temperature difference data, and simultaneously calculate and verify the adjusted real-time flow rate and actual heat exchange load, so that the actual heat exchange load continuously approaches the target demand load. When the load deviation enters the preset control dead zone range, the actuator stops operating and maintains the current valve opening.

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